Edger means for bending the edge of a can blank



Aug. 12, 1958 R. E. RENARD 2,847,051 EDGER MEANS FOR BENDING THE EDGE OFA CAN BLANK Original Filed Ray 3 1954 2 Sheets-Sheet 1 INVENTOR. ROLANDE- REWARD l4 3 I J ByWLwQL ATTORNEY Aug. 12, 1958 R. s. RENAR D EDGERMEANS FOR BENDING THE EDGE OF A CAN BLANK Original Filed May 3, 1954 2Sheets-Sheet 2 Whv INVENTOR.

1 ROLAND E.

REWARD ATTORNEY United States Patent EDGER MEANS FOR BENDING THE EDGE OFA CNN BLANK Roland E. Renard, Los Gatos, Calif., assignor to NationalCan Corporation, Chicago, 111., a corporation of Delaware 7 Claims. (Cl.153-16) This invention relates to a new and improved can body maker andmore particularly to the edger station thereof. Reference is made to mycopending application Serial No. 427,244, filed May 3, 1954, for CanMachine and Method, of which the present application is a division.

A modern can bodymaker is a machine having a series of longitudinallyspaced work and idle stations and feed mechanism to advance body blanksfrom station to station. Body blanks are fed into a laterally offsethopper at the front of the machine, withdrawn from the hopper one at atime, and advanced transversely to the center of the machine. Uponreaching the center of the machine, the blanks are then fedlongitudinally from station to station. The principal stations of themachine comprise the following:

Cross feed station 1 at which the blanks are fed from the hoppertransversely to the center of the machine.

Idle station 2 to provide room for the adjacent work stations.

Notching station 3 at which the corners of one longitudinal edge of theblank are notched to eliminate unnecessary overlapping when the blank isformed in a cylinder and the other longitudinal edge is slit adjacentthe corners to facilitate subsequent bending of the edges.

Idle station 4 similar to station 2.

Edging station 5 at which the longitudinal edges of the blank are bentbackwardly in hooks. In the instant machine the edging operation isperformed at a single station, whereas in other bodymakers the edging ismany times performed at two stations.

Idle station 6 is similar to stations 2 and 4.

Forming station 7 where the blank is formed into a cylinder, the hookedlongitudinal edges being interlocked and the seam secured by hammering.

The advance of the can-body blank from station to station longitudinallyof the machine is accomplished by a pair of feed bars which reciprocatelongitudinally on opposite sides of the center. The feed bars carryopposed feed fingers, corresponding to the number of stations, which, onthe feed stroke of the machine, engage the body blank and move itforwardly one station.

A further feature of the invention resides in the construction of theparts of the edger station. In many conventional bodymakers, edging ofthe blank is accomplished at two different stations. In such bodymakersthe first edging operation involves a vertical movement of an edgingsteel which bends the marginal edge of the blank at approximately aright angle to the blank. At the second edging station of such priorconstructed bodymakers, the edge of the blank is bent backward so thatit assumes an acute angle with respect to the blank. The employment of atwo-stage edger increases the number and complexity of the working partsand, more importantly, increases the necessary length and weight of thefeed bars, a principal limitation on the maximum speed of the machine.

In some prior constructed bodymakers, edging is performed at a singlestation by means of a complex mechanical movement which moves an edgingsteel first vertically and then inwardly relative to the blank. Suchsingle station edging mechanisms have required use of reciprocatingparts and complex, slow-speed movements which have limited the maximumspeed of operation of edging and the capacity of the machine. Thepresent invention employs a single edging station, but employs at thesingle station two edging steels which operate in sequence, one bendingthe edge of the blank approximately at right angles and the otherbending the edge back at an acute angle with respect to the blank. Thetwo steels are driven by eccentrics at a higher rate of speed than if acam shaft were employed.

Other objects of the present invention will become apparent upon readingthe following specification and referring to the accompanying drawingsin which similar characters of reference represent corresponding partsin each ofthe several views.

In the drawings:

Fig. l is a fragmentary top plan of a can bodymaker in which the presentinvention is employed;

Fig. 2 is a fragmentary side elevation of the structure of Fig. 1; and

Figs. 3, 4 and 5 are transverse vertical sectional views takensubstantially along the lines 33, 44 and 5--5, respectively, of Fig. 2and showing the mechanism in different positions of its cycle ofoperations.

The machine incorporating the present invention is exceedingly complexand consists of various sub-assemblies, many of which are conventionalin the can-making art. Accordingly many of the parts of the machine havebeen eliminated or described only very briefly.

As will be understood by one skilled in the can-making art, in the canbodymaker metal blanks are fed into the machine one at a time and at onestage of operation of the machine notches and slits are cut on oppositeside edges of the body blank at a notching station. Thereafter blank 20is moved by feed fingers 72 to the edger station and the blank isclamped against feed table 39 on side table 23 by a longitudinallyextending clamp bar 156 on each side of the machine.

On each side of the machine longitudinally extending side table 23supports a longitudinal, horizontal side shaft 27. Side tables 23 havevertical side rails 28 which extend rearwardly behind the notchingstation to the forming station and are located inwardly and above shaft27.

zontally reciprocating feed bar 56, driven by means not shown in timedrelation to rotation of side shaft 27 The outer edges of feed bars 56fit into longitudinally, horizontally extending ways 68 formed asgrooves in the inner vertical faces of rails 28 of side tables 23 andare held therein by retaining plates 69 which are connected to the railsby screws 71.

Pressure bar spine 30 has a plurality of laterally projecting ears 81which are connected to longitudinally extendiug skid supports 82. Belowsupports 82 are short, horizontal, longitudinal presser bar skids 83,each presser bar skid being a short longitudinal, horizontal foot havingvertical pins 84 biased downward by springs 86 from supports 82 so as tocreate a drag restraining any tendency of the moving blank 20 to slideby inertia beyond its proper station.

The outer edge of the clamp bar is formed in a wedge with its upper edge157 directed inwardly in an acute angle to co-act with the secondoperation edger steel to bend the edge of the blank at the same angle ina manner hereinafter set forth. Clamp bars 156 are actuated in a shortarcuate travel by yoke 158 which is pivotally mounted on pivot shaft 159journalled in bosses 161 on side table 23. A vertically movableadjustment screw 162 On either side of the machine is a longitudinallyhorithreaded into longitudinal connecting portion 163 of yoke 158contacts the upper end of cam rod 164, the lower end of which isprovided with a cam follower roller 166 which engages cam 167 on sideshaft 27. Cam rod 164 has an enlarged guide 168 which is received withina bore in bracket 169 which is attached to side table 23. Spring 171 isinterposed between guide 168 and a cap 172 threaded into bracket 169 tokeep follower 166 in contact with cam 167. Timing of cam 167 is suchthat during the cycle when the blank is feeding from station to station,clamp bar 156 is raised in the position shown in Fig. 3 of theaccompanying drawings. When the blank has come to rest, cam rod 164 islifted, which causes yoke 158 to rock about pivot shaft 159 until theclamp assumes the position shown in Figs. 4 and 5, whereupon it clampsthe blank between clamp bar 156 and feed table 39.

At the edger station are first operation and second operation edgersteels 173 and 174, respectively, extending longitudinally. There is aset of steels on each side of the machine. The first operation steel 173is held in a rocker arm 176 which is pivoted on pivot shaft 159 and theend of the rocker arm opposite first steel 173 is provided with a boss177 through which fits wrist pin 178 which also passes through thebifurcated end 179 of a fitting 181 on the upper end of connecting rod182. The lower end of connecting rod 182 is formed with an eccentricstrap 183 and cap 184 which engage the eccentric 186 on side shaft 27.As side shaft 27 revolves, rocker arm 176 rocks around pivot shaft 159causing a cycle of movement of the first operation steel, as hereinafterdescribed.

Second operation steel 174 is likewise engaged by second rocker arm 187which is pivotally mounted on pivot shaft 159, the opposite end of whichis formed with a boss 188 through which fits wrist pin 189 which alsopasses through the bifurcated upper end 191 of second connecting rod192, the lower end of which is provided with an eccentric strap 193 andcap 194 which pass around second eccentric 196 on side shaft 27. As sideshaft 27 revolves, second steel 174 is rocked through a cycle ofoperations hereinafter described in detail.

First operation steel 173 comprises three parts, an uppermost curvedflank 201 which has its center of curvature on the axis of pivot shaft159, a transverse shoulder 202 and a lower flank 203. During the feedcycle of the machine, the first steel is approximately in the positionshown in Fig. 3 whereby upper flank 201 is at the level of feed table 39so that the outer edge of blank 20 contacts the flank and is thuscentered relative to the machine. After clamp bar 156 has clamped theblank against the side table, as shown in Fig. 4, the cycle of the firststeel brings shoulder 202 upward so that it engages the bottom surfaceof the edge of blank 20 and bends it upwardly against the outer edge ofclamp bar 156. One feature of the present machine is that the axis ofrighthand pivot shaft 159, as shown in the accompanying Figs. 3, 4 and5, is located above feed table 39. Hence pivotal movement of shoulder202 produces a glancing, upward, inward movement rather than a straightvertical movement and the bending of the blank 20 is less likely tocause rupture than in ordinary edger mechanisms.

After first steel 173 has risen to the position shown in Fig. 4, itbegins to retract until it reaches the position shown in Fig. at thebottom of its cycle and is out of the way to permit second operationsteel 174 to come into operative position.

The lower edge 204 of second operation steel 174 has a slanted surfacewhich is complementary to the surface 157 of clamp bar 156, the anglebeing the desired ultimate angle of the bent-back edge of blank 20relative to the main body of the blank. Second operation steel I74 movesdown to the position shown in Fig. 5 and bends the edge of blank 20 backagainst clamp bar 156 to the position shown.

After the sequence of operation shown in Fig. 5 has been completed,second operation steel 174 moves upward until it eventually reaches theposition shown in Fig. 3 and clamp 156 moves upward to the positionshown in Fig. 3. Upon release of blank 20 from between the clamp bar andfeed table, the blank is free to move longitudinally of the machine.

Steels 173 and 174 shown in Figs. 3-5, inclusive, are on the righthandside of the machine as viewed from the front. On the righthand side, theedge of the blank is bent upwardly and inwardly. On the lefthand side ofthe machine, however, the edge of the blank is bent downwardly andinwardly. Accordingly, on the lefthand side of the machine (not shown)pivot shaft 159 is below the level of feed table 39; first and secondoperation steels 173 and 174 are inverted from the position shown inFigs. 3-5 and the edge of feed table 39 is formed wedge-shaped,resembling lower edge 157 of clamp bar 156. The construction of thelefthand side of the edger station will be apparent to one skilled inthe can-making art from a consideration of the description andillustration of the righthand side of the machine which has been setforth.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity ofunderstanding, it is understood that certain changes and modificationsmay be practiced within the spirit of the invention and scope of theappended claims.

What is claimed is:

1. Edger means for a can bodymaker for bending the edge of a can blankbackwards at an acute angle comprising a first steel, a second steel,means for mounting said first and second steels, for pivotal movement,clamp means for holding a can blank with one edge engaging said firststeel, means for separately pivoting said steels in sequence to firstmove said first steel in one direction against the edge of said blank tobend said edge approximately at about said clamp means, and then to movesaid second steel in the opposite direction to bend said edge backwardat an acute angle about said clamp means.

2. Edger means according to claim 1 in which is provided a pivot shaftfor said means for mounting said first and second steels, said pivotshaft being offset from the plane of said bank in the direction in whichsaid edge is bent.

3. Edger means according to claim 1 in which said first steel has alocating flank curved about the center of pivotal movement of said firststeel, said flank being adapted to restrict outward sideward movement ofthe blank prior to clamping of said clamp means.

4. Edger means according to claim 1 in which said first steel has alocating flank curved about the center of pivotal movement of said firststeel, said flank being adapted to restrict outward sideward movement ofthe blank prior to clamping of said clamp means, and a shoulder behindsaid flank in respect to the direction of working movement of said firststeel, said shoulder being adapted to engage the edge to be bent andbend said edge.

5. Edger means according to claim 1 in which said first steel has alocating flank curved about the center of pivotal movement of said firststeel, said flank being adapted to restrict outward sideward movement ofthe blank prior to clamping of said clamp means, and a shoulder behindsaid flank in respect to the direction of working movement of said firststeel, said shoulder being adapted to engage the edge to be bent andbend said edge, said edger means further comprising a pivot shaft forsaid means for mounting said first steel, the center line of said shaftbeing offset from the plane of said blank in the direction in which saidedge is bent so that said shoulder moves against said edge in an inward,glancing stroke.

References Cited in the file of this patent UNITED STATES PATENTS CurtisAug. 15, 1916 LaXo Dec. 13, 1955

